Artificial lighting for plant growth may be energy intensive. Conventional light sources emit electromagnetic spectrum in a broad range of visible and non-visible light, but only part of this spectrum is relevant for photosynthesis. Therefore, for plant growth, much of the energy delivered by lighting sources is wasted on these non-optimized spectrum emissions. Further energy waste may occur due to the use of various types of conventional high pressure lighting, such as high pressure sodium (HPS) lights, which require energy for ignition. This energy is not converted to light, but is instead shed as wasted heat and/or as spectral emissions not utilized during the photosynthesis process.